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Sure, they may take your stuff or spend too much time in the bathroom. But in the long run, having siblings while growing up increases your chance for a successful marriage later in life, one study finds.

Researchers from Ohio State University have found that for each sibling a child has growing up, that person’s chance of divorce falls by two percent. The findings come after studying data in the General Social Survey, which revealed that families of seven or more tend to encourage greater socialization and openness, factors that the researchers argue better serve people in their future romantic lives.

The survey included interviews with 57,000 people at 28 points between 1972 and 2012. The benefits of having more siblings appeared across all generations, the researchers said.

"We expected that if you had any siblings at all, that would give you the experience with personal relationships that would help you in marriage," Donna Bobbitt-Zeher, co-author of the study and assistant professor of sociology at Ohio State's Marion campus, said in a statement.

Having only one or two siblings doesn’t generate the same magnitude of results, added Doug Downey, co-author of the study and professor of sociology at Ohio State.

In order to maximize one’s chances of maintaining a successful marriage — among countless other factors, ostensibly — a family should have around seven children. Researchers found incremental benefits leading up to the seventh child, but the trajectory leveled off at that point. More siblings didn’t hurt a person, but they didn’t significantly help either.

Controlling for socioeconomic status (SES), education, family structure, age at marriage, and race, the team found the same relationship between sibling count and divorce.

Still, Bobbitt-Zeher is cautious to assign too much weight to their findings, as divorce often comes as the result of many complicated factors.

"There are so many factors that are related to divorce, and the number of siblings you have is just one of them," she said. "There is a relationship between the number of siblings and divorce, but it is not something that is going to doom your marriage if you don't have a brother or sister."

As it turns out, having a sister could be the best predictor for how future relationships will turn out, according to a separate study from the University of Ulster.

Professor Tony Cassidy and a group of researchers from De Montfort University in Leicester questioned 571 young adults between the ages of 17 and 25 about their emotional well-being and family make-up. Overwhelmingly, sisters leaned on one another for support — especially in lower-SES families — but also showed more independence and “keen on achievement,” according to the findings.

Sisters also provided broader benefits to the family overall. Brothers, meanwhile, offer little of the same benefits.

“Sisters appear to encourage more open communication and cohesion in families. However, brothers seem to have the alternative effect,” Cassidy said, noting that boys tend to stonewall their feelings and shut down.

Overall, he said, sisters tend to bring out the best in people — making them more likely to penetrate an emotionless exterior and find one’s true feelings.

“Emotional expression is fundamental to good psychological health,” Cassidy said, “and having sisters promotes this in families.”